Transfer case fluid option?

I used this in my transfer case, RAVENOL MTF-3 75W Gear Oil, cost $35 to have it shipped to my door. It has been recommended on here a few times.
I have used 4wd many times in the winter at below 0f temps with no issues.

https://www.ravenolamerica.com/passenger-car-products/75w-gear-oil-ravenol-mtf-3/

 

There's definitely peace of mind not questioning these things and spending the premium for OEM. Sometimes it's for a benefit, sometimes it's for just the peace of mind and offers no real added value. I've just found Lexus guys who have used the liqui moly 5100 in their transfer cases without issue. Combined with liqui moly listing toyota's t-case fluid on their site as a suitable replacement that's what I'm going with, don't see any concern or reason not to at this point. Only $8.89 from FCP right now and even with 3qts of redline MT90 added I'm still spending less than one can of OEM t-case fluid.

Even worst case - I'm taking less risk and closer to OEM spec with this $9 bottle for the t-case than the guys putting their

$29 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 GL5 fluids from the diffs in theirs. My truck deserves at least close to OEM spec or better too

 

CCN guy says multigrade gear oil is fine for transfer case. See at 7 min 55 sec.

https://youtu.be/3le9ZT5HUlk

 

I was under the impression 3rd gen transfer cases had brass components therefore GL5 would not be recommended. Also another video posted about a T-case teardown they speak on the oil pump and heavier oil could strain it and that's the reason for 75W. I'm not sure if the liquid gold is GL4 or GL5, doesn't specify, but the top two recommendations the MT-LV and Ravenol are both GL4 as well as other 3rd party reference oils are all GL4 (including the liqui moly & Eurol too).

I've liked this guys videos, but sometimes he seems to go on a tangent without actually saying much or giving context... like when a school assignment has a 1000 word requirement but you're already done at 300 the rest is fluff.

 

Royal Purple Synchromax works as well and is on store shelves everywhere. Zero shifting issues this brutal winter.

 

A lot of people say a lot of things. The second gen transfer case (VF2BM) is very similar to ours with a similar pump, a synchro, etc. it called for

$29 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 GL4 or 5. There have been too many cases of success with multi grade oil in the 3rd gen to be concerned about problems arising from it.

In reality, it is an extremely simple box of gears with a chain. The fluid used is not really very critical.

 

I'll report back on the liqui moly after some days in the snow & below freezing temps

 

All transfer cases in vehicles I've owned have brass synchro's. 1978 Chevy pickup, 1977 Toyota FJ40, 2002 Tacoma. All list gear oil aka the same stuff you put in the differentials.

 

Did the '78 Chevy have the NP203 or NP205?

 

205

 

While I know this thread is more about the t-case than transmission, I've gone down the rabbit hole of trying to figure this all out. Why Toyota doesn't specify beyond 75W for t-case I'm still not sure, but one thing I can promise you is I do NOT trust a dealer. Just because they put the same bulk fluid in all 3 doesn't mean it's the best thing for it. Even the extra care powertrain warranties don't go past 125k miles to my knowledge, and most people opt for the standard 60k that's included, so why would they care about putting their bulk fluid in there if it still runs?

IDK about you guys, but the dealer never checks up on me to see how the truck is doing or cheers me on for planning to make it last without visiting their service dept into the 200k+ range. They DO always check up to see if I want to trade it in for a new truck while keeping my payment the same for just another 72 months! IMO, the TLDR is using the same gear oil in all 3 won't cause an immediate issue and helps their margins, so it's not their problem.

I read through this that was pretty helpful. This guy seems to be more qualified to speak on it: https://rawze.com/forums/uploads/201803/post_697_1521003200_edf17701a235c056b69a1a6df6a495da.pdf

"When we use a GL-5 product in a transmission that requires GL-4, we normally find 2 to 4 times as
much copper in the used oil as we would with a GL-4 product (with used oil analysis). Eventually the
synchronizers wear to the point that they no longer make contact with the other half of the cone,
bottoming out before stopping the opposing gear."

edit: We all know this wouldn't even be a discussion if the 75W toyota fluid was priced reasonably. Everything after is just trying to justify the cost or not.

 

The extreme pressure sulfur additive (why diff oil is stinky) that a hypoid gearset needs erodes brass and bronze over time.

 

What I do is I buy 2 bottles of MT-LV, store the leftover. Next 5 changes, you only need to buy 1 bottle! @3JOH22A is correct about the thicker fluid causing shifting issues when subzero. I experienced it first hand.

 

I'm confused as to why there's so much confusion about this. Makes me nervous that I missed something since I just changed my transfer case oil today. 2022 TRD Off Road automatic. I went with what's specified in the owner's manual: LF 75W. GL-5 is specified for the front and rear diffs, not the transfer case according to my owner's manual.

 

^LF 75W is the correct fluid. Its high cost (if bought from US dealer) has people looking for suitable alternatives.

GL5 was specified for 1st gen and 2nd gen transfer cases, so there are 20 years of historical knowledge causing confusion. 2015 manual for example:

 

You have nothing to be concerned about as you stuck to the user manual.

The new transfer cases on all toyota / lexus were apparently designed by a different company, BorgWarner, and that's when the change happened as they no longer call for GL5 or

$29 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90. (edit for conflicting info)

I'm sure Toyota changed the user manual for a reason with the new t-cases. I trust the engineers at Toyota, but obviously do not trust the dealer. Dealers can't even change anyone's oil without over-torquing the oil filter housing, why people take their word over Toyota's I'm not sure.

 

The Tundra got a Borg Warner case in 2014. The Tacomas all have Aisin cases still. The Aisin cases have all been a similar design for a long time and they really don’t care much as to what you use for fluid as long as you use something in the general correct category, aka some sort of gear oil.

 

I'm finding conflicting info on this one. Any ref I can check on this?

& I understand you're a rebel against the user manual. Have to ask why the SAE 140 in the transmission & GL6 in the diffs? Genuinely curious if it's personal bias or if there's an argument & secret sauce there. 140 in the transmission sounds mushy or to cover up a problem before selling...

 

Tech stream will show what transfer case design each is. 2nd gen had the VF2BM, 3rd gen was VF2CM, 4th gen is VF2DM.

The borg warner transfer case was a very specific change for the tundra 2014 facelift. It had a new electromagnet in the synchro system I believe. I don’t know much about it. They updated the tundra to 75W LF that year.

Tacomas switched to 75W LF for 2016. FJs switched to 75W LF in 2010, after not undergoing any transfer case changes. While the Tacoma started using the new fluid on a “new” transfer case model, there is nothing in that transfer case model that requires the special fluid. It might shift a bit better with the expensive stuff in extreme cold weather.

I’m not a rebel against the OM, I’m just not afraid to experiment and try different things. The SAE 140 in the transmission was an experiment. I first tried 85W-90 GL4 and it felt better than stock, but it was a bit stiff when cold. I was headed into summer of 2023 so I tried SAE 140 just out of curiosity. It shifted great, but then it got cold outside and I wanted to try something else. Certainly nothing to cover up in selling. I landed on Driven brand 80W-90 GL4 as my favorite trans fluid. I’ve also tried Ravenol synthetic blend

$29 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 and Motorcraft 75W-90 and I didn’t like either of them very much, comparatively.

GL6 in the diff is nothing special. That is just an extra spec the fluid meets. It is still a GL5 compatible fluid. Essentially it is just the fluid that Revolution recommends people run in their gears.

 

I use Ravenol 75W for my transfer case fluid. Same specs as the OEM fluid and much less expensive.